Many brands, one software

What is PLC-PROG?

Ladder Logic is still the language of choice for most PLC-programmers and it is used in the ‘traditional’ way, without the use of new ‘object oriented’ capabilities that the IEC- 61131-3 standard provides. However, common paradigms (Ladder Diagram, Grafcet, etc.) have currently reached their limits, as modern industry requires more agile PLC- programs. Currently, PLCs must not only control the installation (which may include multiple processes running in parallel), they must also support an interactive dialogue with operators, and need to exchange data with other control equipment or the Internet. In addition, complex programs developed with, for example, Ladder Logic diagrams, easily extend beyond several pages of graphical code or are so obscure that they become unusable. Ladder Diagrams were not designed for these complex requirements, causing significant software development problems: weak software structure, low levels of software re-use, poor data structure, limited support for sequencing, limited execution control, cumbersome arithmetic operations and no native support for external visualisation and communications. This means two main drawbacks: 1) Programming costs are extremely high in terms of time efforts for the development and maintenance, and 2) Security of the PLC operation is very difficult to guarantee due to the difficulties in verification of Ladder-based programs (highly relevant for industrial applications).

In order to solve all these limitations, the consortium is developing a new and innovative PLC brand independent programming tool called PLC-PROG. This tool defines a new paradigm for programming PLCs based on a friendly interface where the user just needs to drag and drop graphical objects for constructing complex programs. The main innovations the PLC-PROG editor software will incorporate are the following:

A unified programming environment valid for different PLC brands. PLC-PROG will fully integrate the IEC-61131 standard set by the EC, increasing programming features in PLCs. Programs generated within the PLC-PROG framework will run on any PLC brand compliant with the standard, without any modification after post processing.

Health and Safety: It is critical that PLC programs are reliable, well-tested and understood by a wide range of industrial personnel, not only by programmers. PLC-PROG will increase worker safety by producing more reliable PLC programs for controlling automated equipment at the work site.

PLC-PROG will improve various efficiency levels in development and maintenance: A decrease of 45% in maintenance time (including SCADA-PLC interactions), a 40% decrease in development time and 40% increase on code reuse are considered for the use of PLC-PROG in comparison to current PLC programming systems.

The program is able to translate the graphical view into a code adapted for a particular brand. The editor generates the OPC objects for proper communication between the PLC and the SCADA simplifying its further development.

The research leading to these results has received funding from the European Union's Seventh Framework Programme managed by REA- Research Executive Agency, FP7/2007-2013 under Grant Agreement no. 243484